【摘要】：隨著人類對(duì)水體富營養(yǎng)化環(huán)境問題的關(guān)注以及對(duì)環(huán)境質(zhì)量要求的提高,凈化含磷污廢水迫在眉睫。尋求高效、低廉的除磷材料倍受研究者的關(guān)注。新型材料納米零價(jià)鐵因其比表面積大,吸附能力強(qiáng)而被廣泛用作吸附劑。本文利用XRD、 XPS、TG/DTG、SEM、TEM、BET等表征手段研究了銅陵天然褐鐵礦及菱鐵礦的礦物組成及其形貌形態(tài)特征,并通過熱處理方式獲得褐鐵礦、菱鐵礦納米結(jié)構(gòu)化相變零價(jià)鐵。通過靜態(tài)實(shí)驗(yàn)研究了不同因素(煅燒溫度、初始pH值、反應(yīng)時(shí)間、初始磷濃度、氧氣總量、干擾離子對(duì)納米鐵除磷效率的影響以及反應(yīng)動(dòng)力學(xué)、吸附平衡的研究。同時(shí)將納米零價(jià)鐵作為動(dòng)態(tài)柱填料并探究其除磷性能。得出以下結(jié)論：(1)銅陵天然褐鐵礦主要由針鐵礦(90wt%)和石英組成,褐鐵礦晶體呈針狀和片狀,具納米尺寸,集合體呈筍狀和球狀；熱處理促使針鐵礦進(jìn)一步納米結(jié)構(gòu)化相變形成零價(jià)鐵,具多孔結(jié)構(gòu)、高比表面積特征。(2)銅陵天然菱鐵礦礦石主要成分為菱鐵礦(FeCO3),除此之外還含有少量的針鐵礦、黏土、石英等雜質(zhì)。菱鐵礦呈菱面體形態(tài),樣品中存在的葉片狀形態(tài)的物質(zhì)主要為伊蒙黏土礦物,針狀、棒狀形態(tài)的礦物為菱鐵礦經(jīng)風(fēng)化氧化形成的針鐵礦。(3)當(dāng)煅燒溫度達(dá)550℃及以上,氫氣流速為180mL/min,氫氣分別還原天然褐鐵礦和天然菱鐵3h可以完全轉(zhuǎn)變成納米零價(jià)鐵。通過BET數(shù)據(jù)分析和實(shí)驗(yàn)結(jié)果證明,隨著煅燒溫度升高,納米鐵對(duì)磷的去除效率先升高后逐漸降低。要保證納米零價(jià)鐵除磷效果最佳,氫氣還原天然鐵礦制備納米零價(jià)鐵最佳煅燒溫度點(diǎn)是550℃。(4)通過靜態(tài)實(shí)驗(yàn),考察了不同煅燒溫度、初始pH值、氧氣總量、初始濃度、干擾離子等對(duì)納米零價(jià)鐵除磷效果的影響,通過實(shí)驗(yàn)確定去除效果的最佳條件,并進(jìn)一步分析了納米零價(jià)鐵除磷的機(jī)理。結(jié)果顯示,在弱酸且溶解氧存在的條件下,本文兩種材料制備出的納米零價(jià)鐵除磷效率達(dá)95%及以上。在納米零價(jià)鐵除磷過程中,反應(yīng)時(shí)間、初始磷濃度、pH值、溶解氧量對(duì)去除率影響很大。而除磷效果基本不受反應(yīng)溫度的影響。(5)氫氣還原褐鐵礦制備納米零價(jià)鐵作為動(dòng)態(tài)柱填料凈化模擬含磷(5mmg/L)廢水可運(yùn)行1年以上,磷去除效率超過99.5%,出水磷濃度達(dá)到地面水體環(huán)境質(zhì)量II類標(biāo)準(zhǔn)(0.025mg/L)。
[Abstract]:With the attention to eutrophication environment and the improvement of environmental quality, it is urgent to purify the wastewater containing phosphorus. The search for high efficiency and low-cost phosphorus removal materials has attracted the attention of researchers. Nanocrystalline zero-valent iron is widely used as adsorbent because of its large specific surface area and strong adsorption capacity. In this paper, the mineral composition and morphology of natural limonite and siderite in Tongling were studied by means of XRD, XPS,TG/DTG,SEM,TEM,BET and other characterizations. Through heat treatment, limonite and siderite nano-structured phase change zero valent iron were obtained. The effects of different factors (calcination temperature, initial pH value, reaction time, initial phosphorus concentration, total oxygen, interference ions) on phosphorus removal efficiency, reaction kinetics and adsorption equilibrium of nanocrystalline iron were studied by static experiments. At the same time, nanocrystalline zero valent iron was used as dynamic column filler and its phosphorus removal performance was investigated. The main conclusions are as follows: (1) Tongling natural limonite is mainly composed of goethite (90 wt%) and quartz. The limonite crystal is acicular and flake with nanometer size and the aggregate is bamboo shoot and globular. Heat treatment promotes goethite to form zero-valent iron with porous structure and high specific surface area. (2) the main component of Tongling natural siderite ore is siderite (FeCO3), in addition to a small amount of goethite and clay, An impurity, such as quartz. Siderite is in the rhombohedral form, and the material in the leaf shape of the sample is mainly Aemon clay mineral, acicular and rod-like minerals are goethite formed by weathering of siderite. (3) when the calcination temperature is 550 鈩，

本文編號(hào)：2214364